Compare · updated 2026-11-01
Claude Sonnet vs DeepSeek Flash
Claude Sonnet is better at writing, coding, reasoning, maths; DeepSeek Flash is better at quick answers, structured data, long documents, translation. DeepSeek Flash is the cheaper of the two on output.
Measured quality by task
| Task | Claude Sonnet | DeepSeek Flash | Better |
|---|---|---|---|
| Quick answers | 85/100 | 91/100 | DeepSeek Flash |
| Writing | 93/100 | 87/100 | Claude Sonnet |
| Coding | 94/100 | 85/100 | Claude Sonnet |
| Reasoning | 90/100 | 80/100 | Claude Sonnet |
| Maths | 84/100 | 78/100 | Claude Sonnet |
| Structured data | 88/100 | 92/100 | DeepSeek Flash |
| Long documents | 90/100 | 91/100 | DeepSeek Flash |
| Translation | 86/100 | 90/100 | DeepSeek Flash |
Quality is Nivana’s measured score for each kind of task, from weekly pairwise evals judged by models from several labs. Prices are live AI Gateway list prices per million tokens. Updated 2026-11-01. How this is measured.
Price and context
| Claude Sonnet | DeepSeek Flash | |
|---|---|---|
| Lab | Anthropic | DeepSeek |
| Input per 1M tokens | $2 | $0.3 |
| Output per 1M tokens | $10 | $1.2 |
| Typical chat answer | $0.010 | $0.00129 |
| Context window | 1M | 1.05M |
| Router picks it for | 3 of 24 request types | Fallback only |
Which should you use?
Use the one that wins the kind of work you do most, unless the price gap outweighs the quality gap for easy requests. Or don’t choose: Nivana scores both, and the rest of the pool, on every request and sends it to whichever is best for that request.
Questions
Is Claude Sonnet better than DeepSeek Flash?
On Nivana’s weekly evals Claude Sonnet scores higher on 4 of 8 task types (writing, coding, reasoning, maths) and DeepSeek Flash on 4 (quick answers, structured data, long documents, translation). Neither is better at everything.
Which is better for coding, Claude Sonnet or DeepSeek Flash?
Claude Sonnet: 94/100 against 85/100 for DeepSeek Flash on Nivana’s coding evals.
Which is better for writing, Claude Sonnet or DeepSeek Flash?
Claude Sonnet: 93/100 against 87/100 for DeepSeek Flash on Nivana’s writing evals.
Which is cheaper, Claude Sonnet or DeepSeek Flash?
DeepSeek Flash: $1.2 per million output tokens against $10 for Claude Sonnet, about 8.3× less. A typical chat answer costs about $0.0013 on DeepSeek Flash and $0.010 on Claude Sonnet.
Or let the router pick, per request
Nivana sends every message to the model that scores best for it, sets how hard it thinks, and tells you which one answered. 2,000 free credits to start, no card.